Phobos - Viking 2 Orbiter

Martian moon Phobos over Ascraeus Mons

Viking 2 Orbiter image of Phobos orbiting over Ascraeus
Mons on Mars. Phobos is about 8000 km below the
spacecraft and 22 km across. Ascraeus Mons is 13,000 km
away and about 300 km at its base, centered at 11 N, 104 W.
North is at 11:30, and Phobos is moving from left to right
relative to the surface.
(Viking Orbiter 304B88)
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